In recent years, building codes in many areas have become increasingly more rigid in requiring that roofs of homes or other buildings be resistant to fire. One way of satisfying this requirement is by treating wooden shingles or shakes with chemicals intended to be fire resistive. Another approach is to utilize shingles or tiles formed of a material other than wood and which is fire resistant. For example, tiles stamped from sheet metal may be utilized. However, such metal roofs as previously designed and as currently available have been more difficult to assemble on a building than would be desired, with resultant excessive overall cost of the completed roof. Much of the difficulty has been caused by the necessity in most instances for attaching to the roof substructure a rather complex grid of intersecting boards as a base to which the metal tiles can ultimately be nailed.